| 摘要 |
<P>PROBLEM TO BE SOLVED: To reduce a delay of information transmission due to a collision of radio signals while extending battery life. <P>SOLUTION: Each fire alarm TR asynchronously transmits a radio signal when any fire alarm TR does not detect a fire. A specific fire alarm (master station) TR1 transmits a synchronizing signal at least one time when any one of the fire alarms TR detects the fire and notifies the other fire alarms TR of fire breaking, and each of the fire alarms (slave station) TR2, ... is allocated to a time slot defined by the synchronizing signal to perform synchronous communication. Further, since the fire alarms (slave station) TR2, ... other than the specific fire alarm (master station) TR1 returns to the specific fire alarm (master station) TR1 a response message for confirming the reception of the radio signal when switching between asynchronous communication and synchronous communication, there is an advantage that asynchronous communication and synchronous communication are surely switched in all of the fire alarms TR. <P>COPYRIGHT: (C)2013,JPO&INPIT |
